Depth Profiling of PAHs Treated with Activated Carbon Using In-situ SPME PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Depth Profiling of PAHs Treated with Activated Carbon Using In-situ SPME PDF full book. Access full book title Depth Profiling of PAHs Treated with Activated Carbon Using In-situ SPME by Ryan Dean Stringer. Download full books in PDF and EPUB format.
Author: Ryan Dean Stringer Publisher: ISBN: Category : Carbon, Activated Languages : en Pages : 0
Book Description
"Novel and efficient methods to measure the bioavailability of hydrophobic organic contaminants (HOCs) in contaminated sediments will play an important role in the acceptance of alternative sediment remediation strategies. In this project, solid phase microextraction (SPME) fibers, protected in perforated steel tubes, were used as in situ passive samplers to measure the treatment of activated carbon (AC) in polycyclic aromatic hydrocarbon (PAH) contaminated sediment. Contaminated sediment was treated with two modes of AC waterjet amendment. In the first treatment, a single 2-min injection was shot into the center of a test vessel and in the second treatment, multiple 7-sec injections in a grid were placed in sediment. In the single injection no treatment was observed 5 cm away from the injection, while at 2.5 cm greater than 90% removal of PAH pore water concentrations were observed. In the multiple injection experiment greater than 90% PAH pore water reductions were observed throughout the test vessel. Highly contaminated and less contaminated sediments were mixed with 0-5% AC by weight to develop AC treatment curves. Over 99% reduction in PAH bioavailability was observed in the less contaminated sediment at 3% AC while 99% removal was never reached even at 5% AC addition in the highly contaminated sediment. Clear treatment curves were observed for both contaminated sediments, though they were very different. In situ equilibration times were 120,215 and 250 hours for phenanthrene, pyrene and benzo(a)Anthracene respetively [sic]. The results show that in situ SPME is a viable method to observe AC treatment and evaluate reductions in bioavailability"--Abstract, Leaf iv
Author: Ryan Dean Stringer Publisher: ISBN: Category : Carbon, Activated Languages : en Pages : 0
Book Description
"Novel and efficient methods to measure the bioavailability of hydrophobic organic contaminants (HOCs) in contaminated sediments will play an important role in the acceptance of alternative sediment remediation strategies. In this project, solid phase microextraction (SPME) fibers, protected in perforated steel tubes, were used as in situ passive samplers to measure the treatment of activated carbon (AC) in polycyclic aromatic hydrocarbon (PAH) contaminated sediment. Contaminated sediment was treated with two modes of AC waterjet amendment. In the first treatment, a single 2-min injection was shot into the center of a test vessel and in the second treatment, multiple 7-sec injections in a grid were placed in sediment. In the single injection no treatment was observed 5 cm away from the injection, while at 2.5 cm greater than 90% removal of PAH pore water concentrations were observed. In the multiple injection experiment greater than 90% PAH pore water reductions were observed throughout the test vessel. Highly contaminated and less contaminated sediments were mixed with 0-5% AC by weight to develop AC treatment curves. Over 99% reduction in PAH bioavailability was observed in the less contaminated sediment at 3% AC while 99% removal was never reached even at 5% AC addition in the highly contaminated sediment. Clear treatment curves were observed for both contaminated sediments, though they were very different. In situ equilibration times were 120,215 and 250 hours for phenanthrene, pyrene and benzo(a)Anthracene respetively [sic]. The results show that in situ SPME is a viable method to observe AC treatment and evaluate reductions in bioavailability"--Abstract, Leaf iv
Author: Amy J. Forsgren Publisher: CRC Press ISBN: 1482243180 Category : Science Languages : en Pages : 260
Book Description
This book describes the sources of water contamination by PAHs and their transportation and fate in natural aquatic systems. It then discusses, from the analytical chemist’s view, how to determine the presence of PAHs in water and wastewater, and the changes in PAH concentration during treatment processes. The text examines the removal of PAHs using membrane bioreactors and advanced sludge processes, highlighting results from both demonstration and full-scale plants. It also examines the presence of PAHs in conventional wastewater treatment plants, especially in sludge.
Author: Ehsan Mirzaee Publisher: ISBN: Category : Languages : en Pages :
Book Description
Among current technologies used for the treatment of polycyclic aromatic hydrocarbons (PAHs) -contaminated media, adsorption has been reported to offer relatively high PAH removal efficiency while being rapid and cost-effective. Therefore, the main goal of this research was to assess and optimize the adsorption process for the removal of PAHs from contaminated water and soil using recoverable magnetic activated carbon-based composites. In the first phase, 6 different composites, 3 magnetic powder activated carbon (MPAC) composites and 3 magnetic granular activated carbon (MGAC) composites, were synthesized, and then, characterized using XRD, FE-SEM, EDS, and FTIR methods. The adsorption experiments revealed that all the recoverable MPACs and MGACs were capable of removing the PAHs from water, with removal percentages ranging from 87.2 to 99.3%. The PAH-loaded MPAC and MGAC with the highest PAH removal efficiency were also subjected to a series of desorption studies. The results indicated that the PAHs desorption was in the range 38.1-60.1% for low molecular weight (LMW) PAHs and 23.4 to 57.2% for the high molecular weight (HMW) PAHs. In the second phase, the adsorption kinetics and isotherms studies were performed on MPAC synthesized by a precipitation (MPAC-Prec.) method, which showed the highest PAH removal efficiency among the prepared magnetic activated carbons (MACs). The PAHs adsorption by MPAC-Prec. was rapid, reaching equilibrium in 6 h with the removal efficiency ranging from 95.6 to 100.0% under the conditions of this study. Among the studied kinetics models, pseudo-second order fitted the experimental data very well, implying that all the MPAC adsorption sites had an equal affinity for PAHs. The results of the kinetic studies also indicated that the greater molecular weight PAHs had a slower adsorption rate due to the slower transfer of their molecules to the MPAC adsorption sites. With an R2 in the range 0.73-0.96, the Langmuir model described the isotherms adsorption of LMW and HMW PAHs better than the other isotherms models. Furthermore, according to the Langmuir model, the maximum adsorption capacity of MPAC-Prec. was determined to be between 8.7 and 11.4 μg/mg for the LMW PAHs, and 8.4 and 20.2 μg/mg for the HMW PAHs. In the third phase, a series of soil washing tests using MGAC synthesized by co-precipitation (MGAC-CoP) method, were carried out to explore the effect of MAC on the PAHs removal from soil. The employed MGAC was the second most efficient MAC in the PAHs adsorption experiments (first phase of research), and it showed greater recovery from soil washing mixture compared to the MPAC-Prec. in the preliminary tests. The MGAC-CoP composite had a surface area and total pore volume of 837.9 m2/g and 0.5 cm3/g, respectively, which were approximately 10% lower than the bare GAC, according to BET test results. Soil washing parameters were optimized for the treatment of a real contaminated soil, which were MGAC-CoP dose of 2% (w/w), washing time of 24 h, liquid to soil ratio of 15:1, stirring speed of 100 rpm, pH of 8.3, and temperature of 25 ̊C. Under these optimized conditions, an average PAHs removal of 47.4% was obtained. Among the LMW and HMW PAHs, anthracene (ANT), and fluoranthene (FLUO) showed the highest affinity to MGAC during the treatment process, with 57.7% and 67.1% removal from soil, respectively. The thermodynamic studies revealed that the adsorption of the LMW and HMW PAHs onto MGAC in soil washing was non-spontaneous and endothermic as the values of Gibbs free energy (∆G ̊>0) and Enthalpy change (∆H ̊>0) were positive. In the fourth phase, the efficiency of MGAC-CoP in surfactant-enhanced soil washing for the PAH removal and the recovery of the surfactant solution was studied. The effective parameters of soil washing with the surfactant (Tween 80) were assessed using a real contaminated soil sample, and the results showed that 5% Tween 80, a liquid to soil ratio of 10:1, and a 72-hour washing time at 20°C were optimum operating conditions. Under these conditions, the average PAHs removal efficiency was 67.6%, which was higher than the 47.4% obtained for the same soil with no surfactant addition in phase 3. The possibility of recycling and reusing the Tween 80 solution was investigated by adding MGAC-CoP to the soil and surfactant solution mixture during the soil washing process. For this purpose, 5% Tween 80 and 2% (w/w) MGAC were used in 7 successive washing cycles, with no regeneration process for the MGAC composite. The results revealed that the combination of surfactant and MGAC was capable of removing 68.6, 70.7, 70.3, 61.6, 55.5, 50.2, and 39.4% of the PAHs from soil in the 7 washing cycles, respectively. Furthermore, the recycled Tween 80 and non-regenerated MGAC did not produce any waste or effluent after 6 times reuse in the treatment process, while successfully recovered and reused. This implies that soil washing with Tween 80 and MGAC is a very affordable, efficient, and practical method for remediation of PAH-contaminated soils.
Author: Publisher: World Health Organization ISBN: Category : House & Home Languages : en Pages : 488
Book Description
This book presents WHO guidelines for the protection of public health from risks due to a number of chemicals commonly present in indoor air. The substances considered in this review, i.e. benzene, carbon monoxide, formaldehyde, naphthalene, nitrogen dioxide, polycyclic aromatic hydrocarbons (especially benzo[a]pyrene), radon, trichloroethylene and tetrachloroethylene, have indoor sources, are known in respect of their hazardousness to health and are often found indoors in concentrations of health concern. The guidelines are targeted at public health professionals involved in preventing health risks of environmental exposures, as well as specialists and authorities involved in the design and use of buildings, indoor materials and products. They provide a scientific basis for legally enforceable standards.
Author: Robert L. Siegrist Publisher: Springer Science & Business Media ISBN: 1441978267 Category : Technology & Engineering Languages : en Pages : 715
Book Description
This volume provides comprehensive up-to-date descriptions of the principles and practices of in situ chemical oxidation (ISCO) for groundwater remediation based on a decade of intensive research, development, and demonstrations, and lessons learned from commercial field applications.
Author: National Research Council Publisher: National Academies Press ISBN: 030909447X Category : Science Languages : en Pages : 371
Book Description
At hundreds of thousands of commercial, industrial, and military sites across the country, subsurface materials including groundwater are contaminated with chemical waste. The last decade has seen growing interest in using aggressive source remediation technologies to remove contaminants from the subsurface, but there is limited understanding of (1) the effectiveness of these technologies and (2) the overall effect of mass removal on groundwater quality. This report reviews the suite of technologies available for source remediation and their ability to reach a variety of cleanup goals, from meeting regulatory standards for groundwater to reducing costs. The report proposes elements of a protocol for accomplishing source remediation that should enable project managers to decide whether and how to pursue source remediation at their sites.
Author: Bernard H. Kueper Publisher: Springer Science & Business ISBN: 1461469228 Category : Technology & Engineering Languages : en Pages : 759
Book Description
The purpose of this book is to help engineers and scientists better understand dense nonaqueous phase liquid (DNAPL) contamination of groundwater and the methods and technology used for characterization and remediation. Remediation of DNAPL source zones is very difficult and controversial and must be based on state-of-the-art knowledge of the behavior (transport and fate) of nonaqueous phase liquids in the subsurface and site specific geology, chemistry and hydrology. This volume is focused on the characterization and remediation of nonaqueous phase chlorinated solvents and it is hoped that mid-level engineers and scientists will find this book helpful in understanding the current state-of-practice of DNAPL source zone management and remediation.
Author: Ryan Dean Stringer
Author: Ryan Dean Stringer
Author: Amy J. Forsgren
Author: 
Author: Ehsan Mirzaee
Author: 
Author: 
Author: Robert L. Siegrist
Author: National Research Council
Author: 
Author: Bernard H. Kueper